Eurostat is the statistical office of the European Union with a focus on processing and publishing data collected by Member States. The most relevant data sets can be found in the Health sub-section of "Population and social conditions". Look for variables about drugs, tobacco and alcohol use in relation to disabilities and deaths.
Data.gc.ca is an initiative of the Canadian government to make data transparent and more easily accessible. Data sets are typically available as XML-based files. Some are XLS-based and can be read by spreadsheet software. When searching, focus on specific substances of interest, like alcohol or tobacco.
CCSA is a government agency in Canada that partners with other organizations to address issues related to substance use and abuse. The focus is on alcohol, marijuana, and prescription drugs, with a particular interest on trends, mental health, and youth. The Resources section of this website features publications on these topics and contain statistics relevant to substance use researchers.